I love wall dives. If you get your buoyancy just right then with a light current a wall dive can give you some of the best diving there is. You have the whole reef in front of you and over your shoulder is always a chance of something appearing from the deep blue.
Gato Island is a very cool wall dive with some added excitement!
Here is my dive profile from my Suunto D4i computer. Note the details say I dived on air. I actually dived on a 32% Nitrox mix to give extended bottom time but Suunto doesn't allow switching from air (which I used the previous day) to Nitrox within a 24 hour period.... I've no idea why except maybe for very conservative safety reasons).
We rolled out of one of the main boats lighters just after dawn and immediately dropped to a plateau at 12m then off the edge down the wall to 28m. The water was a pleasant 26c (ideal for a 2mm shorty) and visibility was a good 25m.
There was a lot of life on the wall including frog fish and a large banded sea snake.
The best part of the dive was a tunnel straight through the island at about 25m deep. The tunnel was about 3m wide and 60m long. At first the tunnel was pitch black and I was thankful for my torch but soon we saw (literally) light at the end of the tunnel.
We had been warned before we dived that a group of large white tip reef sharks often use the end of the tunnel for sleeping. I love sharks so I was hoping they would be there. And sure enough as I got to the end of the tunnel I disturbed about six of them. The largest being about 2m long. By now there was a strong current on my back so I managed to wedge myself in the tunnel exit and film the sharks as they circled. An awesome end to the dive.